Currently it doesn't present any fill option when WhatsApp requests the 2FA code. The only way to fill it is by opening 1Password app, copying the code and then pasting on WhatsApp, which is a lot of steps.
1Password Version: 8.9.13
Extension Version: Not Provided
OS Version: Android 12
Browser:_ Not Provided
Referrer: forum-search:Is there a way for 1Password to fill the Whatsapp 2FA code in Android?